As previous studies by these investigators and others have indicated that albino and hypopigmented states in man and animals involve systems other than the direct dermal protective effects of melanin, the general objective of this program is to study these relationships in their broad aspects. We wish to establish this program as a center for the study of albinism and hypopigmented conditions. Specifically, we will investigate pigment disorders in man and determine their clinial, epidemiologic, genetic, histologic, ultrastructural and tissue culture characteristics, with emphasis on those disorders of man that manifest the cardinal signs of oculocutaneous albinism, hypopigmentation of skin, hair, and eyes, with decreased visual acuity, nystagmus and photophobia, and increased susceptibility to carcinogenesis. We will investigate the biochemical and/or morphologic basis of these defects. Of particular concern will be the optic neurologic tract defects in hypopigmented conditions, the platelet defects, and chemical, morphologic, and physiologic characteristics, and the increased susceptibility to cancer.